Cisco Systems uBR7246VXR Cabling Guidelines, Power Connection Guidelines for DC-Powered Systems

Power Connection Guidelines for DC-Powered Systems

The DC-input power supply allows the Cisco uBR7246VXR router to operate on either -48 or -60 VDC systems.

Warning	Connect the unit only to DC power source that complies with the safety extra-low voltage (SELV) requirements in
	IEC 60950 based safety standards. Statement 1033

The Cisco uBR7246VXR router (using DC power supplies) is not shipped with wiring to connect to a DC power source. You must provide input, return, and earthing (grounding) wiring at the site, and install and protect the wiring in accordance with local and national wiring regulations.

Cabling Guidelines

When planning the location of a new system, keep in mind signal type, signal speed, and transmission medium, as well as distance limitations for signaling, EMI, and connector compatibility. Use this information as a guideline in planning your network connections prior to installing the Cisco uBR7246VXR router.

Ethernet and Fast Ethernet Connections

The maximum distances for Ethernet and Fast Ethernet network segments and connections depend on the type of transmission cable being used. See Table 2 for the maximum transmission distances between stations.

Table 2	Ethernet and Fast Ethernet Maximum Transmission Distances
Transceiver Speed		Cable Type	Transmission Mode	Maximum Distance Between Stations
10 Mbps		Category 3	Full duplex and half duplex	328 ft (100 m)
10 Mbps		Multimode (MMF)	Full duplex and half duplex	1.2 mi (2 km)
100 Mbps		Category 5	Full duplex and half duplex	328 ft (100 m)
		Category 5e
100 Mbps		Category 6	Full duplex and half duplex	328 ft (100 m)
100 Mbps		MMF	Half	1312 ft (400 m)
			Full	1.2 mi (2 km)
100 Mbps		Singlemode (SMF)	Half	1312 ft (400 m)
			Full	6.2 mi (10 km)

For details about Ethernet 10BaseT and 100BaseTX cables, refer to the Ethernet 100BaseTX and 10BaseT Cables: Guidelines and Specifications document at the following URL:

http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a00801f5d9e.shtml

Coaxial Cable Connections

Keep in mind the following information when you are setting up and cabling your system.

•The length of the cable determines the amount of signal loss.

•Headend-grade cable (quad-shield 59-series minimum) is recommended.

•Do not bend the coaxial cable tighter than the cable manufacturer's specified minimum bend radius.

•Do not tighten cable connections (F connectors) more then 10 to 15 in-lbs (1.73 to 2.31 nm).

•To prevent connection problems, always use the same size coaxial cable. For example, going from a 6-series cable to a 59-series cable may cause reliability issues (intermittent contact) in the headend environment.

6